File not found when using jar

I'm using Eclipse for development. I can run my code inside the Eclipse environment without a problem but when I export the project to a runnable jar, I get a FileNotFoundException when trying to execute the jar file.

Files don't exist inside of Jars; resources do. So don't try to read anything held in the Jar as a File as it simply won't work. The Class class has a getResourceAsStream method and you can use this to get your resource from the Jar, then use an InputStreamReader then a BufferedReader.